user authentication for a network which has windows 2003 server

hi,
Is it possible to configure a user authetication from the windows server.I will make it clear.when a computer switch ON it will search for ip address from the server.If there is dhcp server,it can get ip address from the server.I would like to authenticate the user, when it try to get them ip address from the dhcp server which is configured in windows 2003.In short dhcp server has to get connected with active directory .Is it possible in windows platform